Narrative:Sabena Flight 712 was a non-scheduled international cargo flight from Brussels, Belgium, to Lagos, Nigeria, on behalf of the Federal Government of Nigeria with 34994 kg of cargo on board. The aircraft took off from Brussels at 21:52 hours UTC on 12 July 1968 and routine radio reports were received during the en route phase of the flight. At 03:25 UTC (13 July) contact was made with Lagos approach control. The aircraft gave an ETA at Lagos of 03:55 hours and reported that it was at FL330. A request was then made for the latest Lagos weather and the reply included the following information: wind: 210°/3 kt; visibility: 16 km; cloud: 5/8 stratocumulus 270 m, 7/8 altostratus 2 400 m, temporary thunderstorms, 118 cumulonimbus 2 000 ft; QNH: 1012 mb; temperature 24°. At 03:27 hours the aircraft reported an ETA overhead Ibadan NDB of 03:44 hours in response to a request for this information from Lagos. One minute later it reported that the Ibadan NDB did not appear to be operating. At 03:36 the aircraft requested descent clearance. It was cleared to Lagos at FL60 and commenced the descent from FL330 at that time. Three minutes later the aircraft reported passing Ibadan and descending through FL275 but since it had reported earlier that the Ibadan NDB seemed not to be radiating, it is not known how the position was determined. In reply Lagos approach stated that there was no delay in the approach and that the runway in use was 19. At 03:41 hours, when the aircraft was about 50 miles north of Lagos, it was recleared to 2200 ft on a QNH of 1012 mb and told to report field in sight. Shortly after this interchange the descent was interrupted while the speed decreased to a figure corresponding to the recommended maximum for landing gear extension and this speed was not exceeded for the remainder of the flight. The autopilot was most probably disengaged at this stage of the flight. Subsequent to the speed reduction the rate of descent was re-established to approximately 2000 ft/min and at 03:50 hours the aircraft passed one mile to the east of Lagos Airport whilst on a southerly heading at an altitude of 15000 ft. The aircraft was heard flying over the airport at this time. A procedure turn was made to the south of the airport in the vicinity of the city of Lagos and at its conclusion there was a second interruption in the descent following which the airspeed remained below the maximum for 25° of flap. At 03:54 hours the aircraft passed over the airport northbound at an altitude of 9000 ft maintaining the average rate of descent of 2000 ft/min for a further 2 1/2 minutes. At 03:56 hours a procedure turn was commenced at an altitude of about 5000 ft during which the rate of descent was reduced to 1500 ft/min. The track of the aircraft between its passage over the airport northbound and the commencement of the final procedure turn is almost coincident with the outbound track of the published VOR approach procedure. At 03:57 hours Lagos approach control was informed by the aircraft that it was in the procedure turn and requested to give the wind conditions. In reply control stated that the wind was calm and this was acknowledged. Shortly afterwards approach control instructed the aircraft to report runway in sight and this was also acknowledged. On completion of the procedure turn at an altitude of 1400 ft (a height above the airport of 1268 ft) the airspeed was reduced from 190 kt to a little less than 160 kt and the rate of descent was reduced to 900 ft/min. The heading was stabilized on 197° M and at 03:59 hours the aircraft asked for the runway lights to be put on maximum brightness. Approach control replied that the runway lights were on low intensity non-variable. A transmitter switch was then heard but there was no subsequent message from the aircraft before it crashed about 8 1/2 miles north of the airport approximately on the extended centre line of the runway. All the occupants were killed and the aircraft caught fire immediately and was burnt out.

Probable Cause:

PROBABLE CAUSE: "The accident was caused by the aircraft descending below its minimum safe altitude for reasons that have not been determined."

This map shows the airport of departure and the intended destination of the flight. The line between the airports does not display the exact flight path. Distance from Brussel-Zaventem Airport to Lagos/Ikeja International Airport as the crow flies is 4894 km (3059 miles).Accident location: Approximate; accuracy within a few kilometers.